The color temperature of light in a scene may add a color cast to a captured image (with the image appearing tinted or having an overall color tone). Additionally, different light sources for a scene may cause different portions of an image to have different color casts. For example, a camera flash may add a blue or cool color cast/overall tone, incandescent lighting may add a yellow or warm color cast/overall tone, and outdoor lighting at different times of day and different cloud cover may add a variety of color casts/overall tones.
Devices (such as digital cameras or other devices configured to capture a digital image) automatically may perform white or color balancing. Automatic white balance (AWB) is a process of estimating a color cast of an image based on portions of the image that should be displayed as neutral colors (such as white or shades of gray). A device may attempt to correct the color tone (remove the color cast) of an image when determined that portions of the image that should be neutral colors are not captured as neutral colors.